Apparatus for preparation of textile fabrics for processing



y 30, 1967 R. L. DAVIDSON ETAL 3,322,363

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mm on INVENTORS RALPH L. DAVIDSON BY STANLEY A. SCHMIDT ATTORNEYS UnitedStates Patent 3,322,363 APPARATUS FOR PREPARATION 0h TEX'HLE FABRICS FORPROCESSING Ralph L. Davidson, Southbo-ro, and Stanley A. Schmidt,Northhoro, Mass, assignors to (Turtis d; Marble Co., a corporation ofMassachusetts Filed Feb. 24, 1965, Ser. No. 434,855 11 (llaims. (Cl.242-58.]l)

This invention deals with the processing of textile fabrics, inparticular with apparatus useful to enable such processing to proceedcontinuously and without interruption.

A textile fabric, typically a strip of cloth and hereinafter termed webor fabric as occasion requires, as it is recovered from the loom onwhich it is woven, is of restricted length and too short, by aconsiderable margin, to permit of the economical application to it oftreatment and processing such as brushing, surface shearing (to removetag ends of thread) bleaching, dyeing, printing and the like. To thecontrary, such processes, and especially the chemical processes, canonly be carried out effectively on a continuous basis and withoutinterruption. This requires that the length of the strip of websubjected to the process be many times longer than that of the striprecovered from the loom. It therefore becomes necessary to join the tailend of each short length of web to the lead end of the next one, e.g.,by sewing them together. Unless resort be had to apparatus ofprohibitive complexity and cost, the sewing operation requires that thetwo strip ends to be joined remain stationary while it is in progress,even though, to preserve the integrity of the subsequent processing, thelatter is carried out without interruption on the long strip constitutedof a series of short strips earlier sewn together. This, in turn,requires that a substantial length of the web shall have been placed instorage from which it can be gradually and continuously withdrawn andfed into the continuous processing apparatus. To avoid interruption ofthe processing, the length of the stored portion of the web must exceedthe product of the speed with which the web is advanced through theprocessing apparatus and the time during which its tail end is haltedfor execution of the sewing operation.

Apparatus for accumulating intermediate portions of a web in storage,thus to permit continuous advance of its forward portions andintermittent movement of the successive tail ends of the shorter webstrips of which it is constituted is termed, in the trade, a scray. Ascray may be employed with advantage to facilitate and expedite thejoining together of a number of web strips, each of limited length, andarriving at the scray as individual rolls of moderate diameter, eachwound on a core, to form a single web strip of much greater length andwind it into a roll of much greater diameter, ready for furthercontinuous processing. Because infrequent interruptions of mechanicalprocesses such as brushing, surface shearing and the like, while theycause delays and loss of time, do not degrade the final product, it isadvantageous and economical to follow the action of the scray by suchmechanical processes before the composite strip is finally wound intothe single, large-diameter roll. The latter, when it leaves theapparatus, is then ready for chemical processing.

Accordingly, a more specific object of the invention is to expedite thestrip-joining operations that are performed at the intake of a scray,thus to reduce the amount of web material which the scray is required tostore.

These objects are attained, in the scray in which the invention isembodied, by the provision of mechanism which responds automatically tothe appearance of the tail end of the advancing web, at a positionconvenient to a bench on which it is to be sewn to the lead end of thenext short strip, and holds it there, preventing web movements bothforward and backward. An attendant havingbrought the lead end of thenext short strip to the same bench, the sewing operation can be carriedout in a few seconds. When it has been completed, he has but to push astart button, and advance of the web into storage is resumed; i.e.,before the continuous advance of the long strip into the processingapparatus shall have depleted the stored intermediate portion of theweb.

To avoid unnecessary complexities of the storage apparatus, the force ofgravity is turned to account by arranging that the stored portions ofthe web shall advance in a generally downward direction from intakerollers which place the rearward portions of the web in store, while itsforward portions are continuously drawn out and, finally, wound into alarge roll suitable for chemical processing. Consequently, the intakerollers are located at the top of the apparatus and draw the webvertically upward past the upper parts of the front face of the scrayand across the sewing bench. As the web is thus drawn upwardly, a pointis reached at which the tail end of the web hangs free like a curtain,and commences to rise. When the lower edge of this curtain reaches acertain preassigned height, a photoelectric cell or electric eye,mounted on one side of the web, is exposed to a beam of light from alamp mounted on the opposite side of the web. The current output of thephotocell then energizes a relay which (a) deenergizes the drivingmotor, which comes to rest slowly, as determined by the inertia of itsload and (b) moves an idler or nip roller out of engagement with thedrive roller, thus removing tension from the web. Release of tensionabruptly halts the advance of the Web into storage While the driveroller is still revolving as it decelerates. But, especially in the caseof a web of heavy fabric, the release of tension permits the dependingcurtain of web to drop downward under the influence of its own weight,drawing some of the ac cumulated stored length with it. To prevent thiseven tuality, a brake is applied to the depending web which catches andholds it in the sewing position. The brake is constituted of two rods,the first one fixed slightly to one side of the vertical plane of theweb riser, the second, free to rotate about its axis, riding against theother face of the web riser when it is tensed by the pull of the driverollers. The second rod or roller constitutes the bob of a pendulousbracket that is pivoted in a plane on the first side of the web so that,when the web goes slack due to disengagement of the nip roller from thedrive roller, the combined weights of the bracket. and the second rodbring the latter against the first one, and the web is immediatelynipped between the two rods and so held in place.

As received from the loom on which it is woven the web is wrapped abouta core in the form of a roll of standard, for example twelve inches,diameter. To minimize pauses in the operation of the scray it isprovided, at a convenient location below the sewing bench, with a cradleassembly comprising a first, or waiting, cradle and a second or feedingcradle, together with supports for the two cradles and adjustable guidesfor the web. In operation an attendant, when not otherwise engaged,fetches a new roll from store and places it in the Waiting cradle assoon as it is unoccupied by a prior roll. During this operation, thefeeding cradle supports a prior roll from which the web is being unwoundand fed into the scray. As soon as the exposure of the photocell to thelight beam has stopped the advance of the web and caused its tail edgeto come to rest, the attendant lifts it to the sewing bench, places thelead edge of the web of the new roll over or against it and starts thesewing machine, thus to join the two edges together. When the seam hasbeen sewn, he pushes the new roll from the waiting cradle into thefeeder cradle and starts the drive motor, thus to resume advance of theweb into the scray.

The feeder cradle of the present scray is formed of a number of rollers,their axes lying on a circular arc of diameter such as snugly to embracea standard roll. As the web is fed into the scray, the roll is unwound.As the roll is unwound, its diameter decreases, it sinks ever lower intoits feeder cradle and it revolves ever faster. Eventually, the diameterof the roll becomes so small and its speed of rotation so high, thatwith other scrays, the roll commences to bounce wildly. This bouncingintroduces variations in the tension of the web so such a point that thebrake may operate sporadically and the web may even be torn. Indeed, insome cases the roll may bounce so high as to expose the photoelectriccell to the beam of light from the lamp, thus causing disengagement ofthe idler roller from the drive roller.

With the scray of the invention these eventualities are prevented byproportioning the feeder cradle so that, before the bouncing conditionis reached the roll of web with its core drops through the cradle andinto a pan below it. From there, unwinding continues as before. Anybouncing that may take place is of negligible effect on the tension ofthe web which is now maintained by friction between the web and thecradle rollers between which it passes. Moreover, the feeder cradle nowoperates as a screen to prevent bouncing so high as to risk exposure ofthe photoelectric cell to the light beam.

To ensure that the web which remains wound on the core when the latterdrops through the cradle shall be of a desired length, independent ofthe thickness of the web, the spacing between the two cradle rollersbetween which it drops is adjustable.

With a web of light, loosely woven fabric, a single layer may be ofinsufficient optical density to obstruct the light beam. In the scray ofthe invention undesired halting of the advance of the web due tospurious actuation of thc photocell is restricted to a comparativelysmall fraction of the full unwinding time by locating the photocell andthe lamp at position such that the path of the light beam passes throughthe entire roll. With this arrangement, many layers of web areinterposed in the path of the light beam until at or just before themoment at which the core drops through the cradle. With web fabric ofnormal thickness, however, a single layer suffices to obstruct the lightbeam.

Because of the pauses introduced in the advance of the web into thescray for the sewing operations, the speed of this advance, while it isin progress, must exceed the speed at which the sewn strip of web iswithdrawn from storage. Because of unavoidable hazards of the sewingoperations due, for example, to a broken thread, a damaged needle, orthe like, a sewing pause may occasionally endure for minutes, ascompared with the average pause length of a few seconds. To guardagainst depletion of the stored length of web during such a pause ofabnormal length, the margin of the intake advance speed over thewithdrawal speed must be substantial. When, therefore, no such unduepauses occur, the length of the stored portion of the web may becomeexcessive, with consequent jamming of the web in the scray which mayimpede withdrawal.

With the scray embodying the invention this eventuality is prevented byautomatically and continuously monitoring the amount of web materialcurrently in storage and when on the occasion of the next sewinginterruption, it is found that the scray is filled to capacity,inhibiting resumption of the web-feeding operation, thus to allow theexcess of stored web material to be depleted. The attendant, havingcompleted the sewing operation and, by pushing the start button, engagedthe idler roller with the drive roller, now waits for a few momentswhile the stored material is being depleted. When it has been reduced tothe proper proportions, the full. scray detector recognizes this factand permits the drive motor to start once more. Thereupon operations areresumed.

The various features briefly alluded to above and their interrelationswill be fully apprehended from the following detailed description of ascray embodying the invention, taken in connection with the appendeddrawings in which:

FIG. 1 is a cross-sectional view of the scray of the invention with webbeing fed into it, accumulated in it, and withdrawn from it;

FIG. 2 is a front elevation of a roll-supporting cradle assembly;

FIG. 3 is a cross-sectional view of the support of an end of a cradleroller; and

FIG. 4 is a schematic wiring diagram showing the electrical circuitswhich control the operation of the scray.

Referring now to the drawings, each side of the supporting structure isa frame 10 constituted of steel beams, welded or bolted together in theform of a rectangle. Within the rectangular frame are placed a sequenceof sloped coasting trays 12, 13, 14, here three in number, along whichthe stored portion 16 of the web, bunched, folded and pleated, advancesin a zig-zag and generally downward direction under the influence of itsown weight and of the pull due to steady rotation of a final rollinghead 18 of the peripheral drive type.

Advantageously, mechanical processing apparatus, e.g., a shearing rangemay be interposed between the scray and the rolling head.

At the top of the intake and of the frame is a drive roller 30 which isrotated in a clockwise sense by a motor 32. Its surface is smooth andpreferably polished so that, until the web 34- is pressed against it, itexerts only a negligible pull on the web. To advance the web 34 andidler roller 36 of which the surface is covered with a material of highfriction coeificient such as rubber, mounted on a bracket 38 pivoted tothe frame 10, is urged against the drive roller 39 by a spring 4% thusto seize the web 34 between the two rollers. For this reason, therubber-covered idler roller 36 is termed a nip roller. When the advanceof the web 34 into the scray is to be interrupted, the motor 32 isdeenergized and a solenoid 42 pulls the nip roller 36 out of engagementwith the drive roller 30, whereupon the drive roller continues torotate, while slowing down, without exerting any sensible amount of pullon the web 34. Indeed, the pull may be so small as to be less than thepull of gravity on the depending portion of the web so that, withoutmore, the riser portion of the web might commence to fall and thuswithdraw a considerable length of web from storage in the reversedirection. This is prevented by a pendulous rod or roller 44 which,hanging in a bracket 46 pivoted to the frame on one side of the web 34,normally rides and rolls against its opposite side but, when the idlerroller 36 is disengaged and the web 34 goes slack, falls against a bar48 past which the web, when it advances, passes. When the pendulousroller 44 thus en gages the bar 48 the web 34 is nipped between them,and so prevented from falling.

Stripper fingers 50, which ride in grooves in the surface of the niproller 36, ensure that the web shall not adhere to its rubber-coveredsurface but, rather, fall into the upper end of the first coasting tray12,

The rolls of web of each particular fabric as they are received from theloom on which the fabric is woven are of like standard diameters. At thefoot of the front face of the frame ltl is a cradle assembly, shown inelevation in FIG. 2, and comprising a first, or waiting cradle and asecond, or feeding cradle, together with supports for both cradles andadjustable guide for the web. The waiting cradle is constituted of a rod52 and a roller 54, spaced apart by a distance somewhat less than thediameter of a new full roll 56 of web.

The feeder cradle is constructed of a plurality of rollers 59, 60mounted on a circular arc of diameter slightly greater than the standardroll diameter. The spacing be tween the two lowermost rollers 60 is mademanually adjustable as by mounting their axes on bearings which may heslid along slotted ways until they are properly aligned at the desiredspacing, whereupon they are seized in position by thumb bolts. Thestructural details are shown in FIG. 3. In this way, the spacing betweenthese two rollers is normally adjusted to exceed, by a safe margin, thediameter of the core 24!- on which the web roll is wound, being smallerby a wide margin than the diameter of a full roll 56. With such aspacing, the roll with its core drops through the cradle only after thegreater part of the strip of which it is constituted has been unwound.

When the web has been completely unwrapped from the core, the latterrolls forward on a sloping tray 61 to a gate 62 against which, alongwith other empty cores, it comes to rest. When a sufiicient number ofempty cores have been thus accumulated at the forward end of the tray61, the attendant opens the gate 62 to allow of their removal. A finfixed to the inside face of the gate ensures against simultaneousemergence of an inconveniently large number of cores.

At a height convenient for working a sewing bench 63 is fixed to thefront face of the frame 10, A sewing machine 64 of the traveling headtype rides on tracks 65 and, when set in operation, advances from sideto side of the bench; i.e., in a direction perpendicular to the plane ofthe drawing. An attendant, having fetched a new full roll from storewhen not otherwise occupied and placed it in the waiting cradle, andhaving unwound a few feet of the length of its web, drawing it towardhim so that it rolls against the roller 54, waits until the advance ofthe strip presently being unwound from the prior roll shall have ceasedand its tail edge come to rest on a tray 67. He then lifts this tailedge to the sewing bench, places the lead edge 58 of the new strip overor against it, and starts the sewing machine. When the seam has beensewn, which takes but a few seconds, he pushes the new roll from thewaiting cradle into the feeder cradle and starts the drive motor 32. Thesolenoid 42 having been deenergized and the nip roller 36 having beenthus reengaged with the drive roller 30, feeding of the web strip intothe scray is resumed.

A lamp 6% is mounted on the frame it) to one side of the feeder cradlein position to direct a beam of light toward a photoelectric cell '70mounted on the other side of the cradle and along a path 72 which passesthrough a substantial part of the body of a new web roll and so througha large number of layers of web. Advantageously, this path 72 lies belowthe level of the core 24 of a new full roll, so that the light beam isobstructed by many layers of web until the nearly empty roll with itscore drops through the cradle. After this has happened the light beam,except in the case of a Web 56 exceptionally thin or of loosely wovenfabric, remains obstructed by the riser portion 34 of the web until thetail edge of the web shall have risen, like a theatre curtain or awindow blind, above the path 72 of the light beam. Thereupon, thephotocell 79 is subjected to the full strength of the light beam, anddelivers a current which, after appropriate amplification, e.g., by anamplifier 71, is of suificient strength to operate a relay 74. Operationof the relay 74 opens the running circuit of the motor 32, and energizesthe solenoid 42 which pulls the nip roller 36 out of engagement with thedrive roller 30. This relieves the tension on the riser portion 34 ofthe web. Three events then happen simultaneously: the drive roller 30slows down and later comes to rest, the advance of the web 34 into thescray ceases abruptly, and the pendulous roller 44 falls into engagementwith the bar 48 thus to prevent the stored web In from pouring out ofthe scray under the influence of the weight of its riser portion 34.

. The relay 74 is of the self-holding variety, and so remains operatedthroughout the web-joining operation despite accidental obscuration ofthe light beam 72. It is released, allowing the idler roller 36 toengage the drive roller 30 and causing the drive motor 32 to start, bypushing the St-art button switch 66 which opens the holding circuit ofthe relay 74.

Convenient speeds of advance of the web 34 into the scray lie in therange 200-500 yards per minute. A speed of advance of 400 yards, or 1200feet per minute, is equivalent to an advance of 18 inches in eachonefifteenth second. The photocell 70 and the amplifier 73 respondessentially instantaneously. Therefore, time delays in the electricalcontrol path are only those of the relay 74 and the solenoid 42. Relaysand solenoids which, together, operate in periods of the order of onefifteenth second are readily available commercially. Consequently, withtwo such devices, it is only necessary, in order that the tail edge ofthe rising web 34 come to a complete stop at a convenient point belowthe sewing bench 63, that the lamp 63 and the photocell 70 be so locatedthat the tail edge of the rising web move out of the path of the lightbeam 72 when it still has 18 inches to go. For this reason, the lamp andthe photocell are mounted about thirty inches below the level of thesewing bench 63.

When, due to the hazards of the sewing operation, a number of longpauses have been necessary, or even a single pause of exceptionalduration, the fabric stored in the scray may be reduced to the dangerpoint, in which case it becomes necessary to stop the rotation of therolling head 18. So, too, when exceptional good fortune has beenencountered and a long sequence of interruptions have all been verybrief, the scray may become filled to capacity with stored fabric, inwhich case it becomes necessary to introduce an artificial pause in theintake feed, to permit the amount of stored fabric to be reduced.Accordingly, the amount of fabric stored in the scray is continuouslymonitored by an empty scray detector and a full scray detector. Theformer comprises a wand which presses gently downward toward the lastcoasting tray 14 and is held out of contact therewith by the fabric 16.When, due to reduction in thickness of pleated web, the wand falls belowits normal position, a microswitch 81 actuates a. relay which stops therotation of the wind-up motor 20. The full scray detector may likewisecomprise a wand 84 of any suitable material, which rides above thepleated fabric 16 stored in the first coasting tray 12 and, when liftedto an abnormal height by pleats, folds and loops of excessivemagnitudes, 'actuates a microswitch 86 which opens the starting circuitof the drive motor 32, but leaves its running circuit unaffected. Themotor 32 therefore continues to run, and to feed web into the scrayuntil operation has again been interrupted for edge sewing. The motor 32then coasts to a stop and comes to rest. Additional storage during theshort interval between determination that the scray is full and the nextinterruption is harmless.

When the excess material stored in the scray shall have beensufiiciently depleted by continued rotation of the rolling head 18 themotor 32 is energized and the relay 74. is released, both by the switch66. Thereupon the roller 30 starts to rotate again, and operation isresumed. In this way, the additional pause required for depletion of theexcess stored material is caused to coincide with a sewing interruptionand possible damage to the web by starting and stopping the rotation ofthe drive roller 30 while the web is being fed into the scray isprevented.

FIG. 4 shows the electrical circuits by which the operations describedabove are instrumented. Power is supplied to the motor 32 through aconventional start-run circuit including a timer relay 90 and a resistor92 through which starting current flows. After a suitable delay, thedelay 90 short-circuits the resistor 92. To start the motor 32, themanual switch 66 and the full scray detector microswitch 86, connectedin series, must both be closed. This prevents starting of the motoruntil any excess material stored in 7 the scray shall have been removedby continued rotation of the rolling head 18.

The relay 74 is provided with three pairs of contacts. Its winding issupplied by the output current of the photocell amplifier 71 through thestart switch 66 and this causes the lower contact pair to close, thus toenergize the solenoid 4 2, and the second contact pair to open. Sincethese are in series with the running circuit of the motor 32, thisremoves power from the motor 32, whereupon it coasts to a stop. Thecontacts of the third pair are interconnected with the relay winding andwith the secondary winding of a transformer 96, in such a way that thesolenoid 42 remains energized and the motor 32 remains deenergizeddespite cessation of the current from the amplifier '71 which may takeplace accidentally and which, in any event, takes place, while the webis at rest for sewing purposes, as soon as the web strip being unwoundfrom a new roll obscures the light beam 72. To ensure against chatteringof the relay 74 a rectifier 98 may be included if desired. The circuitof the holding winding is broken, when operations are to be resumed, byclosure of the starting switch 66 and opening of the holding switch 94,coupled together. The light beam 72 having by now been obscured, thisallows the lower contacts of the relay 74 to open, thus to deenergizethe solenoid 42, and the second contacts to close, thus to enable themotor 32 to run. Impede-d by the inertia of its load, as well as itsown, the motor 32 starts revolving gently, and so avoids tearing of theweb which might take place if resumption of web-feeding wereinstrumented by abrupt engagement of the nip roller 36 with a driveroller 39 already revolving at full speed.

The invention having now been described, what is claimed is:

1. In apparatus for expediting the joining of the tail edge of a stripof web fabric of limited length to the lead edge of a similar strip toform a strip of extended length suitable for subsequent processing inorder that such processing of the extended strip may proceed withoutinterruption, a feeder cradle for supporting a roll of web, wrappedabout a core, a sewing bench above said cradle, a smooth surfaced driveroller above said bench, means for continuously rotating said driveroller, a friction-surfaced idler roller disposed adjacent to said driveroller and normally engaged with said drive roller to nip said webbetween said rollers and advance it steadily, a photoelectric celldisposed on one side of said web, a light source disposed on the otherside of said web and oriented to direct a light beam toward said cell,said beam being normally obstructed by said web, electromagnetic meansfor with drawing said idler roller from engagement with said driveroller in response to current output of said cell which occurs when thetail edge of said web is lifted above the path of said light beam,thereby to stop the roller-driven advance of said web and to relievesaid web of tension, and web-catching means between said bench and saiddriver roller for preventing fall of said web under the influence of itsweight.

2. Apparatus as defined in claim 1 wherein the idler roller withdrawingmeans is characterized by a particular response time and wherein thesource and the cell are located at points such that the path of thelight beam lies below the sewing bench by a distance equal to twice theproduct of said response time by the speed of advance of said webwhereby, when said cell is exposed to said light beam by the rise of thetail edge of said web above its path, said tail edge comes to rest halfway between said cradle and said bench.

3. Apparatus as defined in claim 1 wherein the webcatching meanscomprises a pendulous bracket, pivoted in a vertical plane that islaterally displaced from the vertical plane of rise of a web rising fromsaid bench to said drive roller, a friction bar fixed on the same sideof said web rise plane and normally out of contact with said web, and asmooth roller fixed to the free end of said pendulous bracket and at aheight above said bench such that it bears Til against said fixed barwhen not urged out of contact therewith, whereby a web extending from aroll in said feeder cradle to said drive roller, passing between saidfriction bar and said bracket-supported roller and under tension due tothe pull of said drive roller and the friction of said web roll in saidcradle moves said bracket-supported roller away from said friction bar,thus to permit free upward movement of said web and whereby, when saidtension is relieved by disengagement of said idler roller from saiddrive roller, a part of said web depending downwardly from said driverroller is seized and held between said friction bar and saidbracket-supported roller.

4. In combination with apparatus as defined in claim 1, a motor forrevolving said drive roller, means responsive to the signal delivered bysaid cell for deenergizing said motor, allowing it to coast to a stop,and means for prolonging said deenergized condition of said motor beyondthe point at which said cell signal vanishes due to obscuration of saidlight beam, and manual switch means for terminating said deenergizedcondition.

5. In apparatus as defined in claim 4, a relay having a first, normallyopen contacts, second normally closed contacts, third normally opencontacts and a winding, the first contacts being connected to saidlifting means, the second contacts being connected in series with thesource of energy which supplies said motor, connections for supplyingsaid photocell signal to said winding, said third contacts beingconnected to said winding in a fashion to prolong energization of saidwinding beyond cessation of said signal.

6. In apparatus for expediting the joining of the tail edge of a stripof Web fabric of limited length to the lead edge of a similar strip toform a strip of extended length suitable for subsequent processing inorder that such processing of the extended strip may proceed withoutinterruption, means for supporting a roll of web, a sewing bench abovesaid supporting means, a smoothsurfaced drive roller above said bench,means for continuously rotating said drive roller, a friction-surfacedidler roller above said drive roller and normally engaged with saiddrive roller to nip said web between said rollers and advance itvertically upward, electromagnetic means for lifting said idler rollerout of engagement with said drive roller in response to an electricsignal, means responsive to the arrival of the tail edge of said web ata preassigned location for developing said electric signal, thereby tostop the roller-driven advance of said web and to relieve said web oftension, and web-catching means between said bench and said drive rollerfor preventing fall of said web under the influence of its weight.

7. Apparatus as defined in claim 6 wherein the webcatching meanscomprises a pendulous bracket, pivoted in a vertical plane that islaterally displaced from the vertical plane of rise of a web rising fromsaid bench to said drive roller, a friction bar fixed on the same sideof said web raise plane and normally out of contact with said web, and asmooth roller fixed to the free end of said pendulous bracket and atsuch a height above said bench as to bear against said fixed bar whennot urged out of contact therewith, whereby a web extending from a rollin said cradle to said drive roller, passing between said friction barand said bracket-supported roller and under tension due to the pull ofsaid drive roller and the friction of said web roll in said supportmoves said bracketsupported roller away from said friction bar, thus topermit free upward movement of said web and whereby, when said tensionis relieved by disengagement of said idler roller from said driveroller, a part of said web depending downwardly from said drive rolleris seized and held between said friction bar and said bracket supportedroller.

8. In apparatus which advances a strip of web fabric under tension in avertical plane by seizing it between a revolving driver roller and anidler roller, and in which interruptions of said advance are effected bydisengagement of said idler roller from said driver roller, thusrelieving said tension, means operative when said tension is relieved,for preventing retrograde movement of said web which comprises a roddisposed on one side of the vertical rise plane of said web, a pendulousbracket swingably pivoted on the same side of said vertical rise plane,said bracket bearing a horizontally disposed roller of substantialweight at its lower end and, when said bracket swings free, insubstantially the same horizontal plane as said rod, said web passingbetween said roller and said rod, whereby the tension of said webnormally holds said roller out of engagement with said rod, and whereby,when said tension is relieved by disengagement of said idler roller fromsaid driver roller, the pendulosity of said bracket causes it to fallinto engagement with said rod, thereby to seize said web and to preventretrograde movement thereof.

9. In combination with apparatus for intermittently advancing a strip ofweb fabric in a vertical direction through the agency of a revolvingdrive roller and an idler roller that engages the drive roller to nipsaid strip between said rollers to cause said advance, said idler rollerbeing intermittently disengaged from said drive roller, thereby tointerrupt said advance, said interruptions occurring when a substantiallength of said strip hangs vertically downward, means for inhibitingretrograde movement of said strip which comprises a pendulous bracket,pivoted in a vertical plane that is laterally displaced from thevertical plane of rise of said strip, a friction bar fixed below saiddrive roller and on the same side of the rise plane of said strip andnormally out of contact with said strip, and a smooth roller fixed tothe free end of said pendulous bracket and at such a height as to bearagainst said fixed bar when not urged out of contact therewith, wherebysaid strip, passing between said friction bar and said bracket-supportedroller and under tension from said drive and idler rollers, moves saidbracket-supported roller away from said friction bar, thus to permitfree upward movement of said strip, out of contact with said frictionbar, said bracket-supported roller meanwhile rolling against a face ofsaid strip and whereby, when said tension is relieved by disengagementof said idler roller from said drive roller, the downwardly hanginglength of said strip is seized and held between said friction bar andsaid bracket-supported roller.

10. In apparatus for expediting the joining of the tail edge of a stripof web fabric of limited length to the lead edge of a similar strip toform a strip of extended length suitable for subsequent processing inorder that such processing of the extended strip may proceed withoutinterruption, means for joining the tail edge of one strip to the leadedge of another strip, a storage tray, a drive roller, means forcontinuously rotating said drive roller including an electric motor, anidler roller normally engaged with said drive roller to nip said webbetween said rollers and feed it into said storage tray, relay means foropening the circuit to said motor in response to an electric signal,means responsive to depletion of the web stored in said tray fordeveloping said electrical signal, thereby to stop the roller drivenadvance of said web, and a holding circuit responsive to said.electrical signal maintaining said circuit open and preventing saidmotor from restarting.

11. In combination with apparatus as defined in claim 10, means fordetecting the presence of an oversupply of web stored in said tray, andmeans under control of said detecting means for preventing reapplicationof power to said motor, thereby preventing start up of said apparatuswhen said storage tray is full.

References Cited UNITED STATES PATENTS 2/1936 Rainey 242-57 X 1/1952Roselius 24258.1

1. IN APPARATUS FOR EXPEDITING THE JOINING OF THE TAIL EDGE OF A STRIPOF WEB FABRIC OF LIMITED LENGTH TO THE LEAD EDGE OF A SIMILAR STRIP TOFORM A STRIP OF EXTENDED LENGTH SUITABLE FOR SUBSEQUENT PROCESSING INORDER THAT SUCH PROCESSING OF THE EXTENDED STRIP MAY PROCEED WITHOUTINTERRUPTION, A FEEDER CRADLE FOR SUPPORTING A ROLL OF WEB, WRAPPEDABOUT A CORE, A SEWING BENCH ABOVE SAID CRADLE, A SMOOTH SURFACED DRIVEROLLER ABOVE SAID BENCH, MEANS FOR CONTINUOUSLY ROTATING SAID DRIVEROLLER, A FRICTION-SURFACED IDLER ROLLER DISPOSED ADJACENT TO SAID DRIVEROLLER AND NORMALLY ENGAGED WITH SAID DRIVE ROLLER TO NIP SAID WEBBETWEEN SAID ROLLERS AND ADVANCE IT STEADILY. A PHOTOELECTRIC CELLDISPOSED ON ONE SIDE OF SAID WEB, A LIGHT SOURCE DISPOSED ON THE OTHERSIDE OF SAID WEB AND ORIENTED TO DIRECT A LIGHT BEAM TOWARD SAID CELL,SAID BEAM BEING NORMALLY OBSTRUCTED BY SAID WEB, ELECTROMAGNETIC MEANSFOR WITHDRAWING SAID IDLER ROLL FROM ENGAGEMENT WITH SAID DRIVE ROLLERIN RESPONSE TO CURRENT OUTPUT OF SAID CELL WHICH OCCURS WHEN THE TAILEDGE OF SAID WEB IS LIFTED ABOVE THE PATH OF SAID LIGHT BEAM, THEREBY TOSTOP THE ROLLER-DRIVEN ADVANCE OF SAID WEB AND TO RELIEVE SAID WEB OFTENSION, AND WEB-CATCHING MEANS BETWEEN SAID BENCH AND SAID DRIVERROLLER FOR PREVENTING FALL OF SAID WEB UNDER THE INFLUENCE OF ITSWEIGHT.